EP0327351A2 - A polymeric blend useful in thin-bed mortar compositions - Google Patents
A polymeric blend useful in thin-bed mortar compositions Download PDFInfo
- Publication number
- EP0327351A2 EP0327351A2 EP89300995A EP89300995A EP0327351A2 EP 0327351 A2 EP0327351 A2 EP 0327351A2 EP 89300995 A EP89300995 A EP 89300995A EP 89300995 A EP89300995 A EP 89300995A EP 0327351 A2 EP0327351 A2 EP 0327351A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- water
- composition
- cellulose ether
- cps
- viscosity
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 239000000203 mixture Substances 0.000 title claims abstract description 84
- 239000004570 mortar (masonry) Substances 0.000 title claims abstract description 25
- 229920003086 cellulose ether Polymers 0.000 claims abstract description 48
- 229920000642 polymer Polymers 0.000 claims abstract description 37
- 229920002125 Sokalan® Polymers 0.000 claims abstract description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 19
- 239000004584 polyacrylic acid Substances 0.000 claims abstract description 16
- 229920000609 methyl cellulose Polymers 0.000 claims abstract description 13
- 239000001923 methylcellulose Substances 0.000 claims abstract description 13
- -1 hydroxypropyl Chemical group 0.000 claims description 16
- GRVDJDISBSALJP-UHFFFAOYSA-N methyloxidanyl Chemical group [O]C GRVDJDISBSALJP-UHFFFAOYSA-N 0.000 claims description 15
- 235000010981 methylcellulose Nutrition 0.000 claims description 11
- 239000001866 hydroxypropyl methyl cellulose Substances 0.000 claims description 9
- 229920003088 hydroxypropyl methyl cellulose Polymers 0.000 claims description 9
- 235000010979 hydroxypropyl methyl cellulose Nutrition 0.000 claims description 9
- UFVKGYZPFZQRLF-UHFFFAOYSA-N hydroxypropyl methyl cellulose Chemical group OC1C(O)C(OC)OC(CO)C1OC1C(O)C(O)C(OC2C(C(O)C(OC3C(C(O)C(O)C(CO)O3)O)C(CO)O2)O)C(CO)O1 UFVKGYZPFZQRLF-UHFFFAOYSA-N 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 8
- 239000011398 Portland cement Substances 0.000 claims description 6
- 239000000945 filler Substances 0.000 claims description 6
- 239000000178 monomer Substances 0.000 claims description 6
- 239000003431 cross linking reagent Substances 0.000 claims description 4
- GJIIAJVOYIPUPY-UHFFFAOYSA-N 2-methylidenebut-3-enoic acid Chemical compound OC(=O)C(=C)C=C GJIIAJVOYIPUPY-UHFFFAOYSA-N 0.000 claims description 3
- 229920001577 copolymer Polymers 0.000 claims description 3
- 229920000896 Ethulose Polymers 0.000 claims description 2
- 239000001859 Ethyl hydroxyethyl cellulose Substances 0.000 claims description 2
- 239000004354 Hydroxyethyl cellulose Substances 0.000 claims description 2
- 229920000663 Hydroxyethyl cellulose Polymers 0.000 claims description 2
- 229920001479 Hydroxyethyl methyl cellulose Polymers 0.000 claims description 2
- 235000019326 ethyl hydroxyethyl cellulose Nutrition 0.000 claims description 2
- 235000019447 hydroxyethyl cellulose Nutrition 0.000 claims description 2
- 229940071826 hydroxyethyl cellulose Drugs 0.000 claims 1
- 229920002959 polymer blend Polymers 0.000 abstract description 2
- 239000004568 cement Substances 0.000 description 11
- LNAZSHAWQACDHT-XIYTZBAFSA-N (2r,3r,4s,5r,6s)-4,5-dimethoxy-2-(methoxymethyl)-3-[(2s,3r,4s,5r,6r)-3,4,5-trimethoxy-6-(methoxymethyl)oxan-2-yl]oxy-6-[(2r,3r,4s,5r,6r)-4,5,6-trimethoxy-2-(methoxymethyl)oxan-3-yl]oxyoxane Chemical compound CO[C@@H]1[C@@H](OC)[C@H](OC)[C@@H](COC)O[C@H]1O[C@H]1[C@H](OC)[C@@H](OC)[C@H](O[C@H]2[C@@H]([C@@H](OC)[C@H](OC)O[C@@H]2COC)OC)O[C@@H]1COC LNAZSHAWQACDHT-XIYTZBAFSA-N 0.000 description 10
- 229960002900 methylcellulose Drugs 0.000 description 10
- 206010016807 Fluid retention Diseases 0.000 description 9
- 230000016615 flocculation Effects 0.000 description 9
- 238000005189 flocculation Methods 0.000 description 9
- 239000000853 adhesive Substances 0.000 description 8
- 230000001070 adhesive effect Effects 0.000 description 8
- 239000000919 ceramic Substances 0.000 description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- 238000002156 mixing Methods 0.000 description 5
- 239000002562 thickening agent Substances 0.000 description 5
- 239000008394 flocculating agent Substances 0.000 description 4
- 239000004615 ingredient Substances 0.000 description 4
- 238000000518 rheometry Methods 0.000 description 4
- 239000004576 sand Substances 0.000 description 4
- 229920006037 cross link polymer Polymers 0.000 description 3
- 230000003311 flocculating effect Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 235000019738 Limestone Nutrition 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 150000001720 carbohydrates Chemical class 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011499 joint compound Substances 0.000 description 2
- 239000006028 limestone Substances 0.000 description 2
- 229920000620 organic polymer Polymers 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 230000008719 thickening Effects 0.000 description 2
- 229920003169 water-soluble polymer Polymers 0.000 description 2
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- CERQOIWHTDAKMF-UHFFFAOYSA-N Methacrylic acid Chemical class CC(=C)C(O)=O CERQOIWHTDAKMF-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 150000001253 acrylic acids Chemical class 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 239000011083 cement mortar Substances 0.000 description 1
- 239000004567 concrete Substances 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000010440 gypsum Substances 0.000 description 1
- 229910052602 gypsum Inorganic materials 0.000 description 1
- 239000011507 gypsum plaster Substances 0.000 description 1
- 239000011396 hydraulic cement Substances 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 239000010445 mica Substances 0.000 description 1
- 229910052618 mica group Inorganic materials 0.000 description 1
- 229920002401 polyacrylamide Polymers 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000007665 sagging Methods 0.000 description 1
- 150000003839 salts Chemical group 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 230000007480 spreading Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 239000000454 talc Substances 0.000 description 1
- 229910052623 talc Inorganic materials 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/04—Portland cements
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B24/00—Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
- C04B24/24—Macromolecular compounds
- C04B24/38—Polysaccharides or derivatives thereof
- C04B24/383—Cellulose or derivatives thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L1/00—Compositions of cellulose, modified cellulose or cellulose derivatives
- C08L1/08—Cellulose derivatives
- C08L1/26—Cellulose ethers
- C08L1/28—Alkyl ethers
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/00034—Physico-chemical characteristics of the mixtures
- C04B2111/00094—Sag-resistant materials
Definitions
- a ceramic tile composition must be easily spreadable and in conjunction the composition must support the tile during the period in which the composition sets.
- a thin-bed mortar composition used to set ceramic tile with a preference for thin-bed mortars contains: sand, cement, and cellulose ethers. It is known that cellulose ethers extend the working time of the thin-bed composition, acting as a water-retention aid.
- cellulose ethers do not contribute to sag resistance, or resistance to movement of the tile that is applied to the thin-bed mortar composition on a vertical surface.
- the carbohydrate is useful as a water-retention aid and as an adhesive.
- This invention concerns a polymer blend useful in thin-bed mortar compositions which comprises a water-soluble cellulose ether with a viscosity from 2,000 to 100,000 cps and a water-insoluble, water-dispersible polymer with a viscosity from 50 to 150,000 cps.
- the water-insoluble, water-dispersible polymer can include an unneutralized polyacrylic acid, that is lightly crosslinked, or a cellulose ether such as methylcellulose.
- this polymeric blend can be used in ceramic tile mortars, cementitious compositions, wall-finishing compounds, cement plasters, and in tape joint compounds.
- the polymeric blend extends the working time of the composition, since the blend has water retention properties.
- the composition e.g., mortar composition
- the blend is easy to use and thin-bed adhesives are possible.
- the blend has strong binding characteristics and it also functions as a sag resistance aid.
- water-insoluble, water-dispersible is meant that the polymer can be water-swellable, due to the level of or type of substitution and is dependent upon the pH of the medium in which the polymer is employed. Typically, the polymer will function as water-swellable in a pH of 12 or greater, but the pH is not a limiting factor. The polymer will absorb at least 50, preferably 2,000 grams (g) of water per gram of polymer.
- the water-insoluble, water-dispersible polymer can include certain cellulose ethers that are water-swellable, or a crosslinked polymer such as a polyacrylic acid, which is also water-swellable due to the crosslinking.
- water-dispersible polymers To function as a water-insoluble, water-dispersible polymer, the crosslinked polymer must be insoluble in water and be unneutralized, even though in the process of utilizing the blend in mortar compositions and the like, the acid does become neutralized.
- acrylic acid in the acid form rather than in the salt form preferably is employed as the water-dispersible polymer.
- water-dispersible polymers can include crosslinked polymers such as polyacrylic acids or water-swellable polymers such as certain cellulose ethers.
- the water-insoluble, water-dispersible cellulose ether is inherently water-swellable and can include a methylcellulose.
- the water-swellability is the greatest at a pH of 12 or greater, although the water-insoluble, water-dispersible cellulose ether can be water-swellable at a pH below 12 depending upon the methoxyl content.
- the water-swellable cellulose ether (at a pH below or above 12) has a methoxyl content from 10 to 25 weight percent, preferably from 18 to 23 weight percent; and has a hydroxypropyl content from 0 to 6 weight percent, preferably from 0 to 4 weight percent. Most preferably, the hydroxypropyl group is not present and only the methoxyl group is present at a concentration of 18 to 23 weight percent.
- the cellulose ether has a viscosity from 50 to 50,000 centipoises (cps).
- the cellulose ether has a viscosity from 100 to 40,000 cps, and most preferably from 500 to 30,000 cps, as a 2 weight percent solution in water at 20°C.
- the cellulose ether swells much more than at a pH below 12, and the viscosity of the cellulose ether is from 500 to 150,000 cps.
- the cellulose ether has a viscosity from 1,000 to 100,000 cps, and most preferably from 2,000 to 50,000 cps, as a 2 weight percent solution in water at 20°C.
- the polyacrylic acid usable in the present invention has a pH less than 7 and is comprised of a copolymer of a vinyl acrylic acid monomer that contains from 0.05 to 2 percent crosslinking agent.
- the vinyl acrylic acid monomer can include, for example, acrylic acids, methylacrylic acids, or their copolymers
- the crosslinking agent can include, for example, trimethyolpropane triacrylate.
- Standard polymerization techniques known in the art may be used to crosslink the monomer to form the polymer. Typically, 0.10 to 0.50 percent of the crosslinking agent is combined with the crosslinkable monomer.
- the monomer must be crosslinked, forming a polyacrylic acid, before employing the polyacrylic acid in mortars, cement plasters and the like.
- the water-swellable polymer must be non-flocculating, meaning a material that does not induce agglomeration of particles present in cementitious compositions, mortars, adhesives and the like. Flocculation is determined by the method described in U.S. Patent 4,021,257. According to the procedures described in U.S. Patent 4,021,257, column 5, a polymer is non-flocculating if its flocculation index is greater than 0.50, preferably 0.60, more preferably 0.70.
- the water-swellable cellulose ethers used herein have a flocculation index of 0.78 and the polyacrylic acid has a flocculation index of 0.65; therefore, both are non-flocculants.
- the water-soluble cellulose ether can be, for example, hydroxypropyl methylcellulose, methylcellulose, ethylhydroxyethylcellulose, hydroxyethylmethylcellulose or hydroxyethylcellulose, and have a viscosity from 2,000 to 100,000 cps, preferably from 4,000 to 50,000 cps.
- a suitable water-soluble methoxyl content is from 16 to 32 weight percent, preferably from 19 to 24 weight percent and the hydroxypropyl content is from 4 to 32 weight percent, preferably from 7 to 12 weight percent.
- the polymeric blend may be employed in various ratios to impart the desired rheological properties. Generally, from 3:1 to 1:3 by weight, respectively, water-soluble cellulose ether to water-insoluble, water-dispersible cellulose ether is operable, and the preferable ratio is from 2:1 to 1:2 by weight of the water-soluble cellulose ether to water-insoluble, water-dispersible cellulose ether. Most preferably, the ratio of water-soluble polymer to water-insoluble, water-dispersible polymer is about 1:1. Generally, the polymeric blend is preblended as a dry powdery mix in the said ratios. The polymeric blend may be added to other ingredients commonly used in forming cementitious or adhesive compositions and the like. However, all the ingredients can be added simultaneously forming the desired composition.
- the polymeric blend of the invention can be employed in ceramic tile mortars, in mortar compositions, wall-finishing compounds, crack fillers, cement plasters, and in tape joint compounds.
- cementitious compositions refer to hydraulic cement and cement is meant to include materials which in admixture with water form a hydrate.
- Common cements can include alumina cement, Portland cement, and gypsum.
- a mortar composition comprising a water-soluble cellulose ether having a viscosity of from 2,000 to 100,000 cps, and a water-insoluble water dispersible polymer with a viscosity of from 50 to 150,000 cps wherein the total amount of the said cellulose ether and polymer is from 0.2 to 2 percent by weight of the dry components of the mortar.
- these water-soluble/-water-insoluble, water-dispersible thickener components constitute from 0.2 to 2 percent, preferably from 0.2 to 1.0 weight percent of the mortar cementitious composition based on dry components.
- the thickener components made up from 0.4 to 0.7 weight percent thereof.
- a typical ceramic tile adhesive composition comprises from 25 to 97 weight percent Portland cement, from 0 to 75 weight percent filler and from 0.2 weight percent to 2 weight percent water-soluble/water-swellable polymeric blend.
- the inert filler is optional, but if desired can include sand limestone, talc, mica, silica, or most any other inert particulate inorganic material.
- cementitious compositions cement plasters or stucco compositions.
- cementitious or stucco compositions can comprise from 50 to 80 weight percent Portland cement, from 20 to 50 weight percent filler such as sand, and from 0.2 to 0.5 weight percent water-soluble/water-insoluble polymeric blend, based on cement.
- surfactants may be added to improve rheology characteristics.
- the composition When preparing a gypsum-plaster composition, the composition is similar to the cementitious compositions except 3 to 4 weight percent of the composition is limestone and about 0.2 weight percent is the water-soluble/water-insoluble polymeric blend. Whereas, when preparing a ceramic tile adhesive composition, the composition is similar to the cementitious composition except about 0.5 weight percent of the water-soluble, water-insoluble polymeric blend is used based on cement.
- the amount of water used with the composition will depend somewhat in the particular use and desired consistency for which the composition is to be employed.
- a dry-set cement mortar composition is prepared by blending the dry ingredients as follows: - 50.0 percent graded Ottowa Sand - 49.5 percent Portland Cement - 0.5 percent total amount of water-soluble/water-swellable polymeric blend* (*the ratio of water-soluble and water-swellable polymer is specified in Table I)
- the mixing operation of mortar with water should be performed slowly until uniform mixing is achieved, and then vigorously, for proper air entrainment and consistency.
- the mixing operation should be performed 5 to 6 minutes after the initial water addition. Shake for 30 minutes and remix before using.
- THICKENER SYSTEM IN TABLE II varying the methoxyl content of the water-dispersible methylcellulose, but also altering the water-soluble polymer.
- compositions in Tables I and II have good rheology and when applied to tiles, there is excellent support; thus the composition has good bonding characteristics. In addition, the compositions retain water sufficiently to allow the mixture to have extended working time.
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- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Structural Engineering (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
- Adhesives Or Adhesive Processes (AREA)
Abstract
Description
- Many adhesives and cementitious compositions such as construction mortars, concretes and plasters are typically formulated with a water-retention aid to improve the characteristics thereof. By employing a water-retention aid, water loss is prevented and the rheological properties are improved. Typically, water-retention aids are used in ceramic tile adhesive compositions to prevent water absorption by the ceramic tile or substrate to which the tile is applied.
- To be functional in the construction industry, a ceramic tile composition must be easily spreadable and in conjunction the composition must support the tile during the period in which the composition sets. Typically, a thin-bed mortar composition used to set ceramic tile with a preference for thin-bed mortars contains: sand, cement, and cellulose ethers. It is known that cellulose ethers extend the working time of the thin-bed composition, acting as a water-retention aid.
- Unfortunately, cellulose ethers do not contribute to sag resistance, or resistance to movement of the tile that is applied to the thin-bed mortar composition on a vertical surface. However, as disclosed in U.S. Patent 4,487,864 when cellulose ethers are crosslinked to form a modified water-soluble carbohydrate, the carbohydrate is useful as a water-retention aid and as an adhesive.
- Another method of controlling sagging is disclosed in U.S. Patent 4,021,257 in which the use of long chain organic polymers, which function as flocculants, aids in sag resistance. In practice, typically, the most operable compositions are mixtures of clays with cellulose ethers and polyacrylamide flocculants, but these are costly and have handling disadvantages.
- Thus, it would be highly desirable to have a composition which has all three properties - good rheology, good bond characteristics, has water-retention properties - and can be used efficiently without cost and handling disadvantages.
- This invention concerns a polymer blend useful in thin-bed mortar compositions which comprises a water-soluble cellulose ether with a viscosity from 2,000 to 100,000 cps and a water-insoluble, water-dispersible polymer with a viscosity from 50 to 150,000 cps. The water-insoluble, water-dispersible polymer can include an unneutralized polyacrylic acid, that is lightly crosslinked, or a cellulose ether such as methylcellulose.
- Generally, this polymeric blend can be used in ceramic tile mortars, cementitious compositions, wall-finishing compounds, cement plasters, and in tape joint compounds. The polymeric blend extends the working time of the composition, since the blend has water retention properties. Thus, the composition, e.g., mortar composition, is easy to use and thin-bed adhesives are possible. By using a water-insoluble, water-dispersible polymer in the polymeric blend, the blend has strong binding characteristics and it also functions as a sag resistance aid.
- By "water-insoluble, water-dispersible" is meant that the polymer can be water-swellable, due to the level of or type of substitution and is dependent upon the pH of the medium in which the polymer is employed. Typically, the polymer will function as water-swellable in a pH of 12 or greater, but the pH is not a limiting factor. The polymer will absorb at least 50, preferably 2,000 grams (g) of water per gram of polymer. In addition, the water-insoluble, water-dispersible polymer can include certain cellulose ethers that are water-swellable, or a crosslinked polymer such as a polyacrylic acid, which is also water-swellable due to the crosslinking.
- To function as a water-insoluble, water-dispersible polymer, the crosslinked polymer must be insoluble in water and be unneutralized, even though in the process of utilizing the blend in mortar compositions and the like, the acid does become neutralized. For example, acrylic acid in the acid form rather than in the salt form preferably is employed as the water-dispersible polymer. Thus, water-dispersible polymers can include crosslinked polymers such as polyacrylic acids or water-swellable polymers such as certain cellulose ethers.
- The water-insoluble, water-dispersible cellulose ether is inherently water-swellable and can include a methylcellulose. The water-swellability is the greatest at a pH of 12 or greater, although the water-insoluble, water-dispersible cellulose ether can be water-swellable at a pH below 12 depending upon the methoxyl content. Additionally, the water-swellable cellulose ether (at a pH below or above 12) has a methoxyl content from 10 to 25 weight percent, preferably from 18 to 23 weight percent; and has a hydroxypropyl content from 0 to 6 weight percent, preferably from 0 to 4 weight percent. Most preferably, the hydroxypropyl group is not present and only the methoxyl group is present at a concentration of 18 to 23 weight percent.
- At a pH below 12, the cellulose ether has a viscosity from 50 to 50,000 centipoises (cps). Preferably, the cellulose ether has a viscosity from 100 to 40,000 cps, and most preferably from 500 to 30,000 cps, as a 2 weight percent solution in water at 20°C. In a pH of 12 or greater, the cellulose ether swells much more than at a pH below 12, and the viscosity of the cellulose ether is from 500 to 150,000 cps. Preferably, the cellulose ether has a viscosity from 1,000 to 100,000 cps, and most preferably from 2,000 to 50,000 cps, as a 2 weight percent solution in water at 20°C.
- The polyacrylic acid usable in the present invention has a pH less than 7 and is comprised of a copolymer of a vinyl acrylic acid monomer that contains from 0.05 to 2 percent crosslinking agent. The vinyl acrylic acid monomer can include, for example, acrylic acids, methylacrylic acids, or their copolymers, and the crosslinking agent can include, for example, trimethyolpropane triacrylate. Standard polymerization techniques known in the art may be used to crosslink the monomer to form the polymer. Typically, 0.10 to 0.50 percent of the crosslinking agent is combined with the crosslinkable monomer. The monomer must be crosslinked, forming a polyacrylic acid, before employing the polyacrylic acid in mortars, cement plasters and the like.
- In addition, the water-swellable polymer must be non-flocculating, meaning a material that does not induce agglomeration of particles present in cementitious compositions, mortars, adhesives and the like. Flocculation is determined by the method described in U.S. Patent 4,021,257. According to the procedures described in U.S. Patent 4,021,257, column 5, a polymer is non-flocculating if its flocculation index is greater than 0.50, preferably 0.60, more preferably 0.70. The water-swellable cellulose ethers used herein have a flocculation index of 0.78 and the polyacrylic acid has a flocculation index of 0.65; therefore, both are non-flocculants.
- The water-soluble cellulose ether can be, for example, hydroxypropyl methylcellulose, methylcellulose, ethylhydroxyethylcellulose, hydroxyethylmethylcellulose or hydroxyethylcellulose, and have a viscosity from 2,000 to 100,000 cps, preferably from 4,000 to 50,000 cps. A suitable water-soluble methoxyl content is from 16 to 32 weight percent, preferably from 19 to 24 weight percent and the hydroxypropyl content is from 4 to 32 weight percent, preferably from 7 to 12 weight percent.
- The polymeric blend may be employed in various ratios to impart the desired rheological properties. Generally, from 3:1 to 1:3 by weight, respectively, water-soluble cellulose ether to water-insoluble, water-dispersible cellulose ether is operable, and the preferable ratio is from 2:1 to 1:2 by weight of the water-soluble cellulose ether to water-insoluble, water-dispersible cellulose ether. Most preferably, the ratio of water-soluble polymer to water-insoluble, water-dispersible polymer is about 1:1. Generally, the polymeric blend is preblended as a dry powdery mix in the said ratios. The polymeric blend may be added to other ingredients commonly used in forming cementitious or adhesive compositions and the like. However, all the ingredients can be added simultaneously forming the desired composition.
- Typically, the polymeric blend of the invention can be employed in ceramic tile mortars, in mortar compositions, wall-finishing compounds, crack fillers, cement plasters, and in tape joint compounds. As used herein, cementitious compositions refer to hydraulic cement and cement is meant to include materials which in admixture with water form a hydrate. Common cements can include alumina cement, Portland cement, and gypsum.
- These thin-bed mortars and cementitious compositions must have strong bonding characteristics known as sag resistance, and additionally, must have water-retention properties to ensure suitable rheology of the composition. Accordingly, in a further aspect of the invention, there is provided a mortar composition comprising a water-soluble cellulose ether having a viscosity of from 2,000 to 100,000 cps, and a water-insoluble water dispersible polymer with a viscosity of from 50 to 150,000 cps wherein the total amount of the said cellulose ether and polymer is from 0.2 to 2 percent by weight of the dry components of the mortar. Typically, these water-soluble/-water-insoluble, water-dispersible thickener components constitute from 0.2 to 2 percent, preferably from 0.2 to 1.0 weight percent of the mortar cementitious composition based on dry components. Preferably, the thickener components made up from 0.4 to 0.7 weight percent thereof.
- In particular, a typical ceramic tile adhesive composition comprises from 25 to 97 weight percent Portland cement, from 0 to 75 weight percent filler and from 0.2 weight percent to 2 weight percent water-soluble/water-swellable polymeric blend. The inert filler is optional, but if desired can include sand limestone, talc, mica, silica, or most any other inert particulate inorganic material.
- Also of interest are cementitious compositions, cement plasters or stucco compositions. Cementitious or stucco compositions can comprise from 50 to 80 weight percent Portland cement, from 20 to 50 weight percent filler such as sand, and from 0.2 to 0.5 weight percent water-soluble/water-insoluble polymeric blend, based on cement. Optionally, surfactants may be added to improve rheology characteristics.
- When preparing a gypsum-plaster composition, the composition is similar to the cementitious compositions except 3 to 4 weight percent of the composition is limestone and about 0.2 weight percent is the water-soluble/water-insoluble polymeric blend. Whereas, when preparing a ceramic tile adhesive composition, the composition is similar to the cementitious composition except about 0.5 weight percent of the water-soluble, water-insoluble polymeric blend is used based on cement.
- Additionally, the amount of water used with the composition will depend somewhat in the particular use and desired consistency for which the composition is to be employed.
- The following examples are provided to illustrate the invention.
- These mixtures are non-flocculating, meaning a material which does not substantially induce agglomeration of particles. A method for determining flocculation activity (flocculation index) is the test described in U.S. Patent 4,021,257. Water-insoluble, water-dispersible organic polymers having a flocculation index, as measured by the test in the patent, of greater than 0.50, may be considered non-flocculants for the purpose of this invention. Polyacrylic acid gives a flocculation index of 0.65 and the methylcellulose used in the said invention gives a flocculation index of 0.78. Thus, the water-insoluble, water-dispersible polymers used herein are non-flocculating.
- The examples in Tables I and II are prepared in the following manner:
- A dry-set cement mortar composition is prepared by blending the dry ingredients as follows:
- 50.0 percent graded Ottowa Sand
- 49.5 percent Portland Cement
- 0.5 percent total amount of water-soluble/water-swellable polymeric blend*
(*the ratio of water-soluble and water-swellable polymer is specified in Table I) - To ensure proper consistency for spreading, 22.0 g of water are added to 100 g of the dry cement blend.
- The mixing operation of mortar with water should be performed slowly until uniform mixing is achieved, and then vigorously, for proper air entrainment and consistency. The mixing operation should be performed 5 to 6 minutes after the initial water addition. Shake for 30 minutes and remix before using.
-
- 1. The thickening system comprises hydroxypropyl methylcellulose and polyacrylic acid (Carbopol® 934, available from the B. F. Goodrich Company). The water-soluble cellulose ether has a viscosity of 5,337 cps as a 2 percent solution and a methoxyl content of 22.1 weight percent with a hydroxypropyl content of 8.1 weight percent to about 12 weight percent. The polyacrylic acid is Carbopol® 934 and has a viscosity of about 416,000 cps at 0.5 percent solids using a Brookfield RVT Viscometer with a number 5 spindle at 2.5 rpm.
- 2. The same as in 1, except the ratio of water-soluble cellulose ether to water-insoluble, water-dispersible polymer is 1.7:1.
- 3. The same as in 1, except the ratio of water-soluble cellulose ether to water-insoluble, water-dispersible polymer is 1:1.
- 4. The same as in 1, except the ratio of water-soluble cellulose ether to water-insoluble, water-dispersible polymer is 1:3.
-
- 5. The thickening system comprises: hydroxypropyl methylcellulose and methylcellulose. The water-soluble cellulose ether, hydroxypropyl methylcellulose has a viscosity of 5337 cps as a 2 percent solution and has a methoxyl content of 22.1 weight percent with a hydroxypropyl content of 8.1 weight percent. The water-insoluble, water-dispersible polymer, methylcellulose, has a viscosity of 2,500 cps as a 2 percent solution and has a methoxyl content of 16.7 weight percent with no hydroxypropyl present.
- 6. The water-soluble cellulose ether has a methoxyl content of 31.4 weight percent with no hydroxypropyl present, and has a viscosity of 3,949 cps as a 2 percent solution. The water-insoluble, water-dispersible polymer, methylcellulose, has a methoxyl content of 22.5 weight percent with no hydroxypropyl present and has a viscosity of 7,500 cps as a 2 weight percent solution.
- 7. The same as in 6, except that the water-dispersible cellulose ether contains 16.7 weight percent methoxyl with no hydroxypropyl present, and has a viscosity of 2,500 cps as a 2 percent solution.
- 8. The same as in 6, except that the water-dispersible methylcellulose has a methoxyl content of 16.8 weight percent with no hydroxypropyl present and the methylcellulose has a viscosity of 300 cps as a 2 weight percent solution.
- The compositions in Tables I and II have good rheology and when applied to tiles, there is excellent support; thus the composition has good bonding characteristics. In addition, the compositions retain water sufficiently to allow the mixture to have extended working time.
-
- A. The control comprises an unneutralized polyacrylic acid Carbapol® 934 with a viscosity of 416,000, at 0.5 percent solids using a Brookfield RVT Viscometer with a number 5 spindle at 25 rpm as a 0.5 weight percent solution. The control has no water retention properties and has extremely poor workability properties.
- B. The control comprises hydroxypropyl methylcellulose with a viscosity of 5,337 cps as a 2 percent solution. The hydroxypropyl methylcellulose has a methoxyl content of 22.1 weight percent and a hydroxypropyl content of 8.1 weight percent.
| Sample No. | Thickener System | Ratio of Water-Soluble Cellulose Ether to Water-Insoluble, Water-Dispersible Polymer | Sag Resistance Value** (mm) | |
| Water-Soluble Cellulose Ether | Water-Insoluble, Water-Dispersible Polymer | |||
| 1 | Hydroxypropyl methylcellulose | Polyacrylic acid | 3:1 | 10.0 |
| 2 | " | " | 1.7:1 | 3.0 |
| 3 | " | " | 1:1 | 2.0 |
| 4 | " | " | 1:3 | 0 |
| A | 0 | *polyacrylic acid | 0:1 | N/A |
| *Control - See page 12 | ||||
| **See page 15 |
Claims (13)
(a) from 50 to 80 parts by weight Portland cement,
(b) from 20 to 50 parts by weight filler,
wherein the amount of components (c) and (d) is from 0.2 to 0.5 parts by weight.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/151,340 US4846889A (en) | 1988-02-02 | 1988-02-02 | Polymeric blend useful in thin-bed mortar compositions comprising a water-soluble cellulose ether and a water-insoluble, but water-dispersible polymer |
| US151340 | 1988-02-02 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0327351A2 true EP0327351A2 (en) | 1989-08-09 |
| EP0327351A3 EP0327351A3 (en) | 1990-10-17 |
Family
ID=22538316
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP19890300995 Withdrawn EP0327351A3 (en) | 1988-02-02 | 1989-02-02 | A polymeric blend useful in thin-bed mortar compositions |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US4846889A (en) |
| EP (1) | EP0327351A3 (en) |
| JP (1) | JPH01279936A (en) |
| BR (1) | BR8900440A (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0508155A1 (en) * | 1991-03-14 | 1992-10-14 | Wacker-Chemie Gmbh | Process for microencapsulation of products emulsive in water but which are not thermoplastic |
| EP0530768A1 (en) * | 1991-09-03 | 1993-03-10 | Hoechst Aktiengesellschaft | Additive combination for improving the workability of water containing building material mixtures |
| EP1278709A4 (en) * | 2000-04-25 | 2005-01-19 | United States Gypsum Co | Gypsum compositions with enhanced resistance to permanent deformation |
| EP1506979A1 (en) * | 2003-08-12 | 2005-02-16 | Wolff Cellulosics GmbH & Co.KG | Cellulose ethers composition for the extrusion of mineral shaped bodies, process for the extrusion of mineral shaped bodies utilising this cellulose ethers composition |
| WO2004065319A3 (en) * | 2003-01-23 | 2005-05-12 | Innovative Constr & Build Mat | Inorganic composite structures enhanced by organic compounds |
| US7419544B2 (en) | 2001-03-02 | 2008-09-02 | James Hardie International Finance B.V. | Additive for dewaterable slurry and slurry incorporating same |
| US7683110B2 (en) | 2005-08-16 | 2010-03-23 | Dow Global Technologies Inc | Preparation of cellulose ether products of increased viscosity and fineness |
| US7704316B2 (en) | 2001-03-02 | 2010-04-27 | James Hardie Technology Limited | Coatings for building products and methods of making same |
| US7727329B2 (en) | 2000-03-14 | 2010-06-01 | James Hardie Technology Limited | Fiber cement building materials with low density additives |
| US7993570B2 (en) | 2002-10-07 | 2011-08-09 | James Hardie Technology Limited | Durable medium-density fibre cement composite |
| US7998571B2 (en) | 2004-07-09 | 2011-08-16 | James Hardie Technology Limited | Composite cement article incorporating a powder coating and methods of making same |
| US8209927B2 (en) | 2007-12-20 | 2012-07-03 | James Hardie Technology Limited | Structural fiber cement building materials |
| US8993462B2 (en) | 2006-04-12 | 2015-03-31 | James Hardie Technology Limited | Surface sealed reinforced building element |
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| JPH0653827B2 (en) * | 1988-04-14 | 1994-07-20 | 第一工業製薬株式会社 | Water-soluble cellulose derivative composition |
| US5026576A (en) * | 1989-11-16 | 1991-06-25 | Benvenuto Francis S | Method and composition for finishing structural building surfaces |
| DE4016979A1 (en) * | 1990-05-25 | 1991-11-28 | Hoechst Ag | THICKENER SYSTEM FOR WATER-CONTAINING MIXTURES |
| US5102462A (en) * | 1990-12-12 | 1992-04-07 | Aqualon Company | High productivity joint compounds |
| US5721221A (en) * | 1991-03-08 | 1998-02-24 | Regents Of The University Of Minnesota | Lowering blood cholesterol levels using water soluble cellulose ethers |
| US5281584A (en) * | 1992-02-28 | 1994-01-25 | The Dow Chemical Company | Effect of particle-size distribution of cellulose ethers on palatability of compositions |
| US5334243A (en) * | 1993-05-04 | 1994-08-02 | The Dow Chemical Company | Crack inhibitor for tape joint compositions |
| US6063856A (en) * | 1993-11-16 | 2000-05-16 | Mass; Warren John | Plaster material for making fresco-like finish |
| US5922788A (en) * | 1995-10-03 | 1999-07-13 | Gotan; Kaneo | Surface coating agent |
| DE19543304B4 (en) * | 1995-11-21 | 2005-06-09 | Skw Bauchemie Gmbh | Additive for water-containing building material mixtures and its use |
| US5653797A (en) * | 1996-04-26 | 1997-08-05 | National Gypsum Company | Ready mixed setting-type joint compound and method of making same |
| JP3936765B2 (en) * | 1996-12-06 | 2007-06-27 | 株式会社エヌエムビー | Additive for cement composition used in pump construction |
| AUPP970099A0 (en) * | 1999-04-09 | 1999-05-06 | James Hardie International Finance B.V. | Concrete formulation |
| AUPQ246599A0 (en) * | 1999-08-26 | 1999-09-16 | James Hardie Research Pty Limited | Extrudable cementitious material |
| ITVA20010015A1 (en) | 2001-06-04 | 2002-12-04 | Lamberti Spa | ADDITIVES BASED ON HYDROXIALKYL DERIVATIVES OF GUARO FOR CEMENTITIOUS MORTARS AND MORTARS CONTAINING THEM. |
| WO2020176211A1 (en) * | 2019-02-28 | 2020-09-03 | Dow Global Technologies Llc | Concrete-forming composition |
| CN110981335A (en) * | 2019-11-28 | 2020-04-10 | 新疆研科节能科技有限公司 | A kind of preparation method and use method of novel concrete anti-cracking cementitious material |
| KR102110294B1 (en) * | 2020-03-17 | 2020-05-13 | 강민규 | Chemical Admixture for Concrete |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2868753A (en) * | 1956-07-03 | 1959-01-13 | American Cyanamid Co | Hydraulic cement compositions containing acrylamide-acrylic acid copolymers and method of making same |
| GB1484454A (en) * | 1973-08-21 | 1977-09-01 | Nat Res Dev | Poly-(carboxylate)cements |
| US3900434A (en) * | 1973-09-04 | 1975-08-19 | Dow Chemical Co | Wallboard tape joint composition and adhesive therefor containing water soluble polyacrylamide, limestone, asbestos, mica and cellulose ether |
| US4043827A (en) * | 1973-11-02 | 1977-08-23 | Tile Council Of America, Inc. | Sag-resistant dry-set mortar composition |
| US4021257A (en) * | 1973-11-02 | 1977-05-03 | Tile Council Of America, Inc. | Cementious composition for use in preparing pointing compounds or mortar compounds |
| US4402752A (en) * | 1981-03-13 | 1983-09-06 | Tile Council Of America, Inc. | Dry-set mortar composition having enhanced bonding characteristics |
| US4487864A (en) * | 1983-04-28 | 1984-12-11 | The Dow Chemical Company | Modified carbohydrate polymers |
| US4594108A (en) * | 1983-09-19 | 1986-06-10 | The Dow Chemical Company | Highly pseudoplastic polymer solutions |
| US4654085A (en) * | 1984-10-11 | 1987-03-31 | Henkel Kommanditgesellschaft Auf Aktien | Additive for cementitious compositions |
| US4596838A (en) * | 1985-05-30 | 1986-06-24 | The Celotex Corporation | Mine stopping caulk |
-
1988
- 1988-02-02 US US07/151,340 patent/US4846889A/en not_active Expired - Fee Related
-
1989
- 1989-02-01 BR BR898900440A patent/BR8900440A/en not_active Application Discontinuation
- 1989-02-01 JP JP1020933A patent/JPH01279936A/en active Pending
- 1989-02-02 EP EP19890300995 patent/EP0327351A3/en not_active Withdrawn
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0508155A1 (en) * | 1991-03-14 | 1992-10-14 | Wacker-Chemie Gmbh | Process for microencapsulation of products emulsive in water but which are not thermoplastic |
| EP0530768A1 (en) * | 1991-09-03 | 1993-03-10 | Hoechst Aktiengesellschaft | Additive combination for improving the workability of water containing building material mixtures |
| US5387626A (en) * | 1991-09-03 | 1995-02-07 | Hoechst Aktiengesellschaft | Additive combination for improving the processing properties of water-containing mixtures of building materials |
| US8182606B2 (en) | 2000-03-14 | 2012-05-22 | James Hardie Technology Limited | Fiber cement building materials with low density additives |
| US7727329B2 (en) | 2000-03-14 | 2010-06-01 | James Hardie Technology Limited | Fiber cement building materials with low density additives |
| EP1278709A4 (en) * | 2000-04-25 | 2005-01-19 | United States Gypsum Co | Gypsum compositions with enhanced resistance to permanent deformation |
| NO343184B1 (en) * | 2000-04-25 | 2018-11-26 | United States Gypsum Co | Curing gypsum-containing composition with improved resistance to permanent deformation, as well as plasterboard |
| EP2253601A1 (en) * | 2000-04-25 | 2010-11-24 | United States Gypsum Company | Accelerators for gypsum compositions with enhanced resistance to permanent deformation |
| US7419544B2 (en) | 2001-03-02 | 2008-09-02 | James Hardie International Finance B.V. | Additive for dewaterable slurry and slurry incorporating same |
| US7704316B2 (en) | 2001-03-02 | 2010-04-27 | James Hardie Technology Limited | Coatings for building products and methods of making same |
| US7993570B2 (en) | 2002-10-07 | 2011-08-09 | James Hardie Technology Limited | Durable medium-density fibre cement composite |
| WO2004065319A3 (en) * | 2003-01-23 | 2005-05-12 | Innovative Constr & Build Mat | Inorganic composite structures enhanced by organic compounds |
| EP1506979A1 (en) * | 2003-08-12 | 2005-02-16 | Wolff Cellulosics GmbH & Co.KG | Cellulose ethers composition for the extrusion of mineral shaped bodies, process for the extrusion of mineral shaped bodies utilising this cellulose ethers composition |
| US7998571B2 (en) | 2004-07-09 | 2011-08-16 | James Hardie Technology Limited | Composite cement article incorporating a powder coating and methods of making same |
| US7683110B2 (en) | 2005-08-16 | 2010-03-23 | Dow Global Technologies Inc | Preparation of cellulose ether products of increased viscosity and fineness |
| US8993462B2 (en) | 2006-04-12 | 2015-03-31 | James Hardie Technology Limited | Surface sealed reinforced building element |
| US8209927B2 (en) | 2007-12-20 | 2012-07-03 | James Hardie Technology Limited | Structural fiber cement building materials |
Also Published As
| Publication number | Publication date |
|---|---|
| BR8900440A (en) | 1989-09-26 |
| EP0327351A3 (en) | 1990-10-17 |
| US4846889A (en) | 1989-07-11 |
| JPH01279936A (en) | 1989-11-10 |
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